U.S. patent number 11,274,633 [Application Number 16/839,437] was granted by the patent office on 2022-03-15 for turbofan comprising a set of rotatable blades for blocking off the bypass flow duct.
This patent grant is currently assigned to AIRBUS OPERATIONS SAS. The grantee listed for this patent is Airbus Operations SAS. Invention is credited to Antoine Boudou, Pascal Gardes, Bastian Sabathier.
United States Patent |
11,274,633 |
Gardes , et al. |
March 15, 2022 |
Turbofan comprising a set of rotatable blades for blocking off the
bypass flow duct
Abstract
A turbofan having a nacelle comprising a slider mobile in
translation between advanced position and retracted positions to
open a window between a duct and the exterior, a plurality of
blades, each one being rotatably mobile on the slider between
stowed and deployed positions, and a maneuvering system moving each
blade and comprising for each blade, a shaft rotatably mobile on
the slider and onto which the blade is fixed, for each shaft, a
balance beam fixed to the shaft and having first and second ends,
for three consecutive balance beams, two connecting rods where the
first connecting rod is mounted articulated between the first
balance beam and the second balance beam, and where the second
connecting rod is mounted articulated between the second balance
beam and the third balance beam, and an actuation system rotating
one of the connecting rods in one direction and in the other.
Inventors: |
Gardes; Pascal (Levignac,
FR), Sabathier; Bastian (Fonsorbes, FR),
Boudou; Antoine (Toulouse, FR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Airbus Operations SAS |
Toulouse |
N/A |
FR |
|
|
Assignee: |
AIRBUS OPERATIONS SAS
(Toulouse, FR)
|
Family
ID: |
67384068 |
Appl.
No.: |
16/839,437 |
Filed: |
April 3, 2020 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20200325785 A1 |
Oct 15, 2020 |
|
Foreign Application Priority Data
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01D
25/24 (20130101); F02K 1/72 (20130101); Y02T
50/60 (20130101); F05D 2260/50 (20130101); F05D
2250/411 (20130101); F05D 2260/606 (20130101); F05D
2220/323 (20130101); F05D 2240/129 (20130101) |
Current International
Class: |
F02K
1/72 (20060101); F01D 25/24 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
French Search Report; priority document. cited by
applicant.
|
Primary Examiner: Legendre; Christopher R
Attorney, Agent or Firm: Greer, Burns & Crain, Ltd.
Claims
The invention claimed is:
1. A turbofan having a longitudinal axis and comprising an engine
core and a nacelle, surrounding the engine core, which comprises a
fan casing, in which a duct for a bypass flow is delimited between
the nacelle and the engine core and in which a flow of air flows in
a flow direction, said nacelle comprising: a fixed structure fixed
to the fan casing, a mobile assembly having a mobile cowl and a
slider, the mobile cowl being fixed to the slider, the slider being
mobile in translation, on the fixed structure, in a direction of
translation between an advanced position, in which the slider is
positioned such that the mobile cowl is moved close to the fan
casing, and a retracted position, in which the slider is positioned
such that the mobile cowl is moved away from the fan casing so as
to define, between them, an open window between the duct and an
exterior of the nacelle, a plurality of blades, each blade
comprising a first end mounted mobile in rotation on the slider
about an axis of rotation and where the blades are gradually offset
angularly about the longitudinal axis, where each blade is mobile
between a stowed position in which the respective blade is outside
the duct and a deployed position in which the respective blade is
across the duct, an assembly of actuators causing the slider to
move between the advanced position and the retracted position, and
vice versa, and a maneuvering system intended to move each blade
from the stowed position to the deployed position and vice versa,
where the maneuvering system comprises: for each blade, a shaft
mounted mobile in rotation on the slider about the axis of
rotation, and onto which the blade is fixed, for each shaft, a
balance beam fixed to the shaft and which has a first end and a
second end which are disposed on opposite sides of said shaft, for
a first balance beam of the balance beams, a second balance beam of
the balance beams and a third balance beam of the balance beams
that are angularly consecutive, two connecting rods where a first
rod of the two connecting rods has two ends, one end of which is
mounted articulated on the second end of the first balance beam and
the other end of which is mounted articulated on the second end of
the second balance beam, and where the second rod of the two
connecting rods has two ends, one end of which is mounted
articulated on the first end of the second balance beam and the
other end of which is mounted articulated on the first end of the
third balance beam, and an actuation system which produces rotation
of one of the balance beams in two directions.
2. The turbofan according to claim 1, wherein, for each of the
connecting rods, the two ends are symmetrical with respect to the
axis of rotation.
3. An aircraft comprising wings and at least one turbofan having a
longitudinal axis and comprising an engine core and a nacelle,
surrounding the engine core, which comprises a fan casing, in which
a duct for a bypass flow is delimited between the nacelle and the
engine core and in which a flow of air flows in a flow direction,
said nacelle comprising: a fixed structure fixed to the fan casing,
a mobile assembly having a mobile cowl and a slider, the mobile
cowl being fixed to the slider, the slider being mobile in
translation, on the fixed structure, in a direction of translation
between an advanced position, in which the slider is positioned
such that the mobile cowl is moved close to the fan casing, and a
retracted position, in which the slider is positioned such that the
mobile cowl is moved away from the fan casing so as to define,
between them, an open window between the duct and an exterior of
the nacelle, a plurality of blades, each blade comprising a first
end mounted mobile in rotation on the slider about an axis of
rotation and where the blades are gradually offset angularly about
the longitudinal axis, where each blade is mobile between a stowed
position in which the respective blade is outside the duct and a
deployed position in which the respective blade is across the duct,
an assembly of actuators causing the slider to move between the
advanced position and the retracted position, and vice versa, and a
maneuvering system intended to move each blade from the stowed
position to the deployed position and vice versa, where the
maneuvering system comprises: for each blade, a shaft mounted
mobile in rotation on the slider about the axis of rotation, and
onto which the blade is fixed, for each shaft, a balance beam fixed
to the shaft and which has a first end and a second end which are
disposed on opposite sides of said shaft, for a first balance beam
of the balance beams, a second balance beam of the balance beams
and a third balance beam of the balance beams that are angularly
consecutive, two connecting rods where a first rod of the two
connecting rods has two ends, one end of which is mounted
articulated on the second end of the first balance beam and the
other end of which is mounted articulated on the second end of the
second balance beam, and where the second rod of the two connecting
rods has two ends, one end of which is mounted articulated on the
first end of the second balance beam and the other end of which is
mounted articulated on the first end of the third balance beam, and
an actuation system which produces rotation of one of the balance
beams in two directions.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims the benefit of the French patent
application No. 1903765 filed on Apr. 9, 2019, the entire
disclosures of which are incorporated herein by way of
reference.
FIELD OF THE INVENTION
The present invention relates to a turbofan which comprises a set
of blades which are mounted so as to be able to rotate in order to
block the duct for the bypass flow, and to an aircraft comprising
at least one such turbofan.
BACKGROUND OF THE INVENTION
An aircraft includes a fuselage to each side of which is fixed a
wing. Under each wing is suspended at least one turbofan. Each
turbofan is fixed under the wing by means of a pylon that is fixed
between the structure of the wing and the structure of the
turbofan.
The turbofan comprises an engine core and a nacelle that is fixed
around the engine core. The turbofan has, between the nacelle and
the engine core, a bypass duct in which a bypass flow flows.
The nacelle comprises a plurality of reversal doors, each one being
mobile in rotation on the structure of the nacelle, between a
stowed position in which it is not in the bypass duct and a
deployed position in which it is positioned across the bypass duct
in order to redirect the bypass flow towards a window which is in
the wall of the nacelle and which is open between the bypass duct
and the outside of the nacelle.
Thus, the bypass flow is redirected to the outside and more
specifically towards the front of the engine in order to generate
reverse thrust. Furthermore, the displacement of each reversal door
is performed using a connecting rod which passes through the bypass
duct in the stowed position and which therefore partially blocks
the bypass duct.
Although reversal doors are entirely satisfactory, it is desirable
to find different mechanisms, in particular mechanisms which are
more lightweight and which do not present any obstruction to the
bypass flow in the stowed position.
SUMMARY OF THE INVENTION
One object of the present invention is to propose a turbofan which
comprises a set of blades which are mounted so as to be able to
rotate in order to block the duct of the bypass flow.
To that end, a turbofan is proposed having a longitudinal axis and
comprising an engine core and a nacelle, surrounding the engine
core, which comprises a fan casing, in which a duct for a bypass
flow is delimited between the nacelle and the engine core, and in
which a flow of air flows in a flow direction, said nacelle
comprising: a fixed structure fixed to the fan casing, a mobile
assembly having a mobile cowl and a slider, the mobile cowl being
fixed to the slider, the slider being mobile in translation, on the
fixed structure, in a direction of translation between an advanced
position in which the slider is positioned such that the mobile
cowl is moved close to the fan casing and a retracted position in
which the slider is positioned such that the mobile cowl is moved
away from the fan casing so as to define, between them, an open
window between the duct and the exterior of the nacelle, a
plurality of blades, each one comprising a first end mounted mobile
in rotation on the slider about an axis of rotation and where the
blades are gradually offset angularly about the longitudinal axis,
where each blade is mobile between a stowed position in which the
blade is outside the duct and a deployed position in which the
blade is across the duct, an assembly of actuators causing the
slider to move between the advanced position and the retracted
position, and vice versa, and a maneuvering system intended to move
each blade from the stowed position to the deployed position and
vice versa, where the maneuvering system comprises: for each blade,
a shaft mounted mobile in rotation on the slider about an axis of
rotation, and onto which the blade is fixed, for each shaft, a
balance beam fixed to the shaft and which has a first end and a
second end which are disposed on either side of said shaft, for a
first balance beam, a second balance beam and a third balance beam
that are angularly consecutive, two connecting rods where the first
connecting rod has two ends, one of which is mounted articulated on
the second end of the first balance beam and the other of which is
mounted articulated on the second end of the second balance beam,
and where the second connecting rod has two ends, one of which is
mounted articulated on the first end of the second balance beam and
the other of which is mounted articulated on the first end of the
third balance beam, and an actuation system which produces the
rotation of one of the connecting rods in one direction and in the
other.
An engine of this kind permits a reduction in mass by replacing the
reversal doors and their drive mechanisms with more lightweight
pivoting blades having a simplified maneuvering system.
Advantageously, the two ends are symmetrical with respect to the
axis of rotation.
The invention also proposes an aircraft comprising at least one
turbofan in accordance with one of the above variants.
BRIEF DESCRIPTION OF THE DRAWINGS
The abovementioned features of the invention, along with others,
will become more clearly apparent on reading the following
description of one exemplary embodiment, said description being
given with reference to the appended drawings, in which:
FIG. 1 is a side view of an aircraft comprising a turbofan
according to the invention,
FIG. 2 is a perspective view of the turbofan according to the
invention in the advanced and stowed position,
FIG. 3 is a perspective view of the turbofan according to the
invention in the retracted and deployed position,
FIG. 4 is a schematic representation of a turbofan according to the
invention, viewed in vertical section, and
FIG. 5 is a perspective view of a maneuvering system according to
the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following description, the terms relating to a position
refer to the direction of flow of the air in an engine which
therefore flows from the front to the rear of the aircraft.
FIG. 1 shows an aircraft 10 that comprises a fuselage 12, to each
side of which is fixed a wing 14 that bears at least one turbofan
100 according to the invention. The turbofan 100 is fixed under the
wing 14 by means of a pylon 16.
FIG. 2 and FIG. 3 show the turbofan 100 which has a nacelle 102 and
a engine core 20 which is housed inside the nacelle 102 and
comprises a fan casing 202. The motor 20 is represented by its rear
exhaust part.
In the following description, and by convention, X denotes the
longitudinal axis of the turbofan 100 that is parallel to the
longitudinal axis of the aircraft 10 oriented positively towards
the front of the aircraft 10, Y denotes the transverse axis which
is horizontal when the aircraft is on the ground, and Z denotes the
vertical axis, these three directions X, Y and Z being mutually
orthogonal.
FIG. 2 and FIG. 3 show the turbofan 100 in two different use
positions, and FIG. 4 shows a schematic representation in section
of the turbofan 100.
The turbofan 100 has, between the nacelle 102 and the engine core
20, a duct 204 in which flows a bypass flow 208 coming from the air
intake through a fan 300, and which therefore flows in the flow
direction from forward to rear.
The nacelle 102 has a fixed structure 206 that is mounted fixed on
the fan casing 202. Here in particular, the fixed structure 206
comprises a front frame 210 mounted around the fan casing 202 and
outer panels 212 forming an aerodynamic surface which are shown as
transparent in FIG. 3, and of which a portion is cut away in FIGS.
2 and 3.
The nacelle 102 has a mobile assembly 214 which has a mobile cowl
216 (also transparent in FIG. 3) of which a portion is cut away in
FIGS. 2 and 3 and which forms the outer walls of the nozzle.
The nacelle 102 also has a slider 218. In this case, the slider 218
is in the form of a cylinder having openwork walls. The mobile cowl
216 is fixed to and downstream of the slider 218 with respect to
the direction of flow of the flow of air in the turbofan 100.
The slider 218 is mounted mobile in translation in a translation
direction globally parallel to the longitudinal axis X on the fixed
structure 206 of the nacelle 102.
The slider 218 is mobile between an advanced position (FIG. 2) and
a retracted position (FIG. 3) and vice versa. In the advanced
position, the slider 218 is positioned as far forward as possible,
with respect to the flow direction, such that the mobile cowl 216
is moved close to the outer panels 212 and to the fan casing 202
and thus forms an aerodynamic surface. In the retracted position,
the slider 218 is positioned as far aft as possible, with respect
to the flow direction, such that the mobile cowl 216 is moved away
from the outer panels 212 and from the fan casing 202 so as to
define, between them, a window 220.
In the advanced position, the mobile cowl 216 and the outer panels
212 extend one another so as to define the outer surface of the
nacelle 102, and the mobile cowl 216 and the fan casing 202 extend
one another so as to define the outer surface of the duct 204.
In the retracted position, the mobile cowl 216 and the fan casing
202, and the outer panels 212, are spaced apart from one another
and define, between them, the open window 220 between the duct 204
and the exterior of the nacelle 102. That is to say, the air from
the bypass flow 208 passes through the window 220 to end up outside
the turbofan 100.
The slider 218 is made to translate by any appropriate means, such
as slideways between the fixed structure 206 and the slider
218.
The nacelle 102 also comprises a set of actuators (not shown) that
move the slider 218 in translation between the advanced position
and the retracted position and vice versa. Each actuator is
controlled by a control unit, for example of the processor type,
which controls the movements in one direction or the other
according to the requirements of the aircraft 10.
Each actuator may, for example, take the form of a double-action
jack (two working directions), of which the cylinder is fixed to
the fixed structure 206 and a rod is fixed to the slider 218.
In order to orient the flow of air leaving the window 220, cascades
can be fixed to the slider 218 facing the window 220.
The fan casing 202 and the outer panels 212 form the upstream
boundary of the window 220 with respect to the direction of flow
and the mobile cowl 216 forms the downstream boundary of the window
220 with respect to the direction of flow.
The nacelle 102 comprises a plurality of blades 250, each being
mounted so as to be able to rotate on the slider 218 about an axis
of rotation that is in this case generally parallel to the
longitudinal axis X. Thus, each blade 250 is able to move between a
stowed position (FIG. 2) in which the blade 250 is outside the duct
204 and a deployed position (FIG. 3) in which the blade 250 is
across the duct 204 in order to redirect the bypass flow 208
towards the window 220.
Each blade 250 is mounted so as to be able to move at a first end
while a second end moves closer to the engine core 20 when the
blade 250 is deployed so as to best block the duct 204.
The blades 250 are gradually offset angularly about the
longitudinal axis X.
The number of blades 250, and the shape of each of these, depend on
the dimensions of the turbofan 100 and on the width of each blade
250 in order that, in the deployed position, the blades 250 block
the majority of the duct 204.
Passage from the stowed position to the deployed position is
brought about by rotation of the blade 250 towards the interior of
the engine 100.
The stowed position can be adopted when the slider 218 is in the
advanced position or the retracted position. The deployed position
can be adopted only when the slider 218 is in the retracted
position.
The slider 218 also has a maneuvering system 400 which moves each
blade 250 from the stowed position to the deployed position.
Thus, operation comprises, starting from the advanced/stowed
position, ordering activation of the actuators to move the slider
218 from the advanced position to the retracted position. During or
at the end of this movement, the maneuvering system 400 moves the
blades 250 from the stowed position to the deployed position.
Conversely, operation thus comprises, starting from the
retracted/deployed position, ordering activation of the actuators
to move the slider 218 from the retracted position to the advanced
position. During or at the start of this movement, the maneuvering
system 400 moves the blades 250 from the deployed position to the
stowed position.
The use of the blades 250 mounted so as to be able to rotate on the
slider 218 makes it possible to lighten the assembly compared to
the use of reversal doors of the prior art.
FIG. 5 shows the maneuvering system 400 which is mounted on the
mobile assembly 214 and more particularly on the slider 218.
For each blade 250, the maneuvering system 400 comprises a shaft
402 which is mounted mobile in rotation on the slider 218 about an
axis of rotation 404, and onto which the blade 250 is fixed. In
FIG. 5, each blade 250 is truncated to simplify the understanding
of the mechanism and only three blades 250 are shown in the stowed
position. Furthermore, in FIG. 5, the slider 218 is seen in cross
section. The axis of rotation 404 is, in this case, generally
parallel to the longitudinal axis X.
For each shaft 402, the maneuvering system 400 also comprises a
balance beam 414a-c which is fixed to the shaft 402 and comprises
two ends 416a-b disposed on either side of said shaft 402. Each
balance beam 414a-c is, in this case, in a plane at right angles to
the shaft 402.
In the embodiment of the invention presented in FIG. 5, the
direction between the two ends is oriented overall radially
relative to the longitudinal axis X. That is to say, a first end
416a is disposed between the longitudinal axis X and the axis of
rotation 404 and a second end 416b is disposed beyond the axis of
rotation 404 relative to the longitudinal axis X. Of course, a
different orientation is possible.
The angular offset of the blades 250 causes the angular offset of
the shafts 402 and of the balance beams 414a-c. For a first balance
beam 414a, a second balance beam 414b and a third balance beam 414c
that are angularly consecutive about the longitudinal axis X, the
maneuvering system 400 comprises two connecting rods 408a-b where
the first connecting rod 408a has two ends, one of which is mounted
articulated on the second end 416b of the first balance beam 414a
and the other of which is mounted articulated on the second end
416b of the second balance beam 414b, and where the second
connecting rod 408b has two ends, one of which is mounted
articulated on the first end 416a of the second balance beam 414b
and the other of which is mounted articulated on the first end 416a
of the third balance beam 414c.
The two connecting rods 408a-b which are fixed onto one and the
same shaft 402 are thus offset on either side of the axis of
rotation 404 and thus a pull on one of the two connecting rods
408a-b will be converted into a push on the other connecting rod
408b-a.
The operation is then as follows in the case of FIG. 5. When a
pulling force is exerted on the connecting rod which is fixed to
the first end 416a of the first balance beam 414a, the latter
pivots about the axis of rotation 404 in the direction of the arrow
420 and at the same time pushes the connecting rod 408a which is
fixed to the second end 416b of the first balance beam 414a, which
causes, in cascade-fashion, the rotation of the second balance beam
414b about its axis 404 and in the same direction (420), and so
on.
The rotation in the direction of the arrow 420 will cause the
displacement of the blades 250 from the stowed position to the
deployed position.
Conversely, when a pushing force is exerted on the connecting rod
which is fixed to the first end 416a of the first balance beam
414a, the latter pivots about the axis of rotation 404 in the
reverse direction of the arrow 420 and at the same time pulls the
connecting rod 408a which is fixed to the second end 416b of the
first balance beam 414a, which causes, in cascade-fashion, the
rotation of the second balance beam 414b about its axis 404 and in
the same direction (the reverse of 420), and so on.
The rotation in the reverse direction of the arrow 420 will cause
the displacement of the blades 250 from the deployed position to
the stowed position.
The maneuvering system 400 also comprises an actuation system 450
which produces the rotational displacement of one of the balance
beams 414a-c, here the first balance beam 414a, in one direction
and in the other by pulling or by pushing one of the ends of said
first balance beam 414a.
In the embodiment of the invention presented in FIG. 5, the
actuation system 450 comprises a rail 452 which is mounted fixed on
the mobile assembly 214, a trolley 454 mounted sliding on the rail
452 and an actuation connecting rod 456 mounted articulated between
the trolley 454 and the first end of the first balance beam
414a.
The actuation system 450 also comprises any appropriate motor means
making it possible to ensure the displacement of the trolley 454
along the rail 452, such as, for example, a cylinder mounted
articulated between the trolley 454 and the mobile assembly 214, a
motor equipped with a rack, etc. The control unit also controls the
motor means.
The link between the trolley 454 and the rail 452 in this case
takes the form of a double dovetail.
The displacement of each blade 250 is then transmitted
step-by-step, and the displacement of one of the balance beams
414a-c will cause the displacement of all of the balance beams
414a-c.
Each articulation between a balance beam 414a-c and a connecting
rod 456, 408a-b, takes the form of a cap whose axis of rotation is
parallel to the longitudinal axis X.
For a good distribution of the loads, the two ends 416a-b are
symmetrical relative to the axis of rotation 404.
The description has been more particularly given in the case of the
first ends 416a which are inside relative to the second ends 416b,
but it is possible to reverse the positions of the ends and
therefore of the connecting rods 408a-b.
Likewise, the description has been more particularly given in the
case where the actuation connecting rod 456 is mounted on the first
end 416a, but it is possible to mount it on the second end 416b
which then becomes a first end and the positions of the connecting
rods 408a-b are then reversed relative to FIG. 5.
Each blade 250 extends in a plane that is overall at right angles
to the longitudinal axis X.
Each blade 250 is mounted mobile on the perimeter of the slider
218. When the blades 250 are in the stowed position, they are
superposed along the longitudinal axis X.
The displacement of all the blades 250 is then relatively simple to
implement because it is sufficient to perform a rotation of the arc
408.
In the embodiment of the invention presented in FIG. 5, the slider
218 comprises a U-shaped profile 219 coaxial with the longitudinal
axis X and open towards the longitudinal axis X. The U-shaped
profile 219 forms a cage in which the blades 250 are mounted mobile
in rotation and where the shafts 402 pass through a wall of the
U-shaped profile 219.
The invention has been more particularly described in the case of a
nacelle under a wing but can be applied to a nacelle located at the
rear of the fuselage.
While at least one exemplary embodiment of the present invention(s)
is disclosed herein, it should be understood that modifications,
substitutions and alternatives may be apparent to one of ordinary
skill in the art and can be made without departing from the scope
of this disclosure. This disclosure is intended to cover any
adaptations or variations of the exemplary embodiment(s). In
addition, in this disclosure, the terms "comprise" or "comprising"
do not exclude other elements or steps, the terms "a" or "one" do
not exclude a plural number, and the term "or" means either or
both. Furthermore, characteristics or steps which have been
described may also be used in combination with other
characteristics or steps and in any order unless the disclosure or
context suggests otherwise. This disclosure hereby incorporates by
reference the complete disclosure of any patent or application from
which it claims benefit or priority.
* * * * *